I. Field of the Invention
This invention relates generally to winding and reeling apparatus, and particularly to an apparatus for winding strip material onto a spool or reel where the rotational velocity of the spool or reel can vary to accommodate a constant feed rate of the strip material.
II. Discussion of the Prior Art
In handling continuous, long lengths of flexible strip material, it is frequently desirable to package quantities thereof in a rolled form. In creating a roll, the strip material is drawn onto to a motor-driven reel or spool from a supply source. If the feed rate of the strip material from the supply source remains fairly constant, provision must be made for changing the speed at which the take-up reel or spool is driven to accommodate the increasing radius of the spooled strip material as the material builds up on the spool.
In prior art systems, expensive electronic servo control loops are frequently used in combination with the reel drive motor to control the speed of the take-up reel drive motor, slowing it down as the effective radius of the spooled strip material increases.
As an example, carpeting is often cut into four-inch wide strips where the strips of carpeting are intended for later use as a base applied to room walls at their intersection with a carpeted floor. Once the carpeting is cut into base strips, the edges thereof must be basted to prevent fraying. A basting strip is sewn to one edge of the carpet strip, using an electric sewing machine. The sewing machine, of course, operates at a generally constant speed as it feeds the basting tape and carpeting strip beneath the reciprocating needle.
The carpet base material is generally sold in 50-foot lengths and is wound as a coil. In the past, to effect winding of carpet base leaving the sewing station, the operation has either been performed manually or through the use of a motor-driven reel whose speed is automatically varied to match the feed rate through the sewing machine as the material builds up on the reel. The motor control circuit commonly includes a suitable sensor for measuring tension and circuitry coupled to the sensor for adjusting the speed of the take-up motor to maintain a relatively constant tension. Alternatively, the carpet strip may be made to form a U-shaped loop between the sewing machine and the take-up reel and a sensor is used to monitor the loop position. The sensor output is then used to vary the speed of the take-up reel motor so that the bottom of the loop remains relatively fixed in position assuring that there will be slake in the strip between the sewing machine and the take-up reel.
There is a need for a simpler, less expensive apparatus for winding up rolls of strip material in a way that adjusts the relative speed of the take-up reel to match the increase in rolled diameter as the strip material builds up on the reel or spool. The present invention provides such a solution.